This vessel bears the seal of Chen Mingyuan, who was active during the Kangxi and Yongzheng reigns (mid-17th to early 18th century). Chen Mingyuan was a very highly regarded ceramic artist, and indeed is generally regarded as one of the finest of all the Yixing potters, and viewed by many as second only to Shi Dabin.
A related Yixing jue with the same treatment of the tops of the posts, and also signed Chen Mingyuan, from the Alice Boney Collection, was illustrated by Terese Tse Bartholomew, I-Hsing Ware, China Institute in America, New York, 1977, p. 53, pl. 29. This example has a plain band on the upper body, and the seal mark is stamped at the top of the leg below the handle. Compare, also, an Yixing jue-form vessel with differently shaped posts, signed Chen Mingyuan, sold at Bonhams Hong Kong, 27 May 2012, lot 550.